Photoluminescence studies of self-assembled InAs quantum dots formed on InGaAs/GaAs quantum well

✍ Scribed by X. Mu; Y. J. Ding; Z. Wang; G. J. Salamo

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 398 KB
• Volume: 2
• Category: Article
• ISSN: 1612-2011
• DOI: 10.1002/lapl.200510037

✦ Synopsis

We have characterized self-assembled InAs quantum dots
grown on the top of a single InGaAs/GaAs quantum well (QD's:QW) by
measuring photoluminescence (PL) spectra as an effective
technique. We have found that the linewidths of the PL peaks for
the QD's:QW are narrower than that for the InAs quantum dots grown
on a GaAs layer by an amount as large as 35 meV. In addition, the
wavelength-integrated PL intensity for the QD's:QW is about twice
higher. Within the lateral plane, the energies for the optical
transitions stay more or less the same for the QD's:QW whereas for
the InAs quantum dots they shift quite a lot from one location to
the next. Furthermore, the QD's:QW exhibit much stronger
band-filling effect than the InAs quantum dots. In order to
explain our experimental results, we have introduced the concept
of a strong coupling between the InAs quantum dots and the
InGaAs/GaAs quantum well strained by the quantum dots.